Archive for the ‘maples’ Category

Extreme Weather: Flash floods in Georgetown (and a tornado?)

July 27, 2010

An unusually large and fierce mass of thunderstorms passed through midcoast Maine last Wednesday. My grandfather recorded 4.75 inches of rain in less than two hours, and small roads washed severely all over town. The stream that flows out of the small pond to the north of the orchard overtopped the road above the middle field, where it passes under the orchard road in a culvert, and a bunch of freshly placed coarse crushed stone washed downstream. Miraculously, the freshly planted middle field adjacent to the stream did not seem to suffer any visible erosion; perhaps it’s the soil, which is still springy with freshly composted sod, or perhaps the young roots of the buckwheat, less than 2 weeks old at the time, were enough to hold it together. The old part of the orchard has a bombproof sod by now, and the younger part is pretty well established with red clover under the pumpkins and this spring’s orchardgrass/timothy/clover treatment at the periphery, so the worst it saw was the windrow of wood chip mulch washed away in a couple of places. The freshly planted maples along the stone wall were more battered, as a sheet of water carrying leaves and small branches appeared to have swept broadly down the hillside, but the small fences we placed around them seemed to have borne the brunt of the assault, and though the young trees were in many cases buried in leaf matter, none seemed irredeemably tattered.

The most dramatic effect occurred where the pond outlet stream passed under the shore road in a 16″ steel culvert; directly after the storm there was no visible effect, but with the passage of a few vehicles over the weekend a yawning sinkhole a foot in diameter and three feet deep opened up right in the roadbed – it’s a wonder it didn’t swallow up somebody’s axle. The subterranean excavation extended most of the way across the road around and above the culvert, which was largely exposed as seen through the sinkhole – the bottom of the culvert must have rusted out, and this allowed water to run underneath it and undermine it. This was confirmed by the discovery of some rusty chunks of corrugated metal in the outwash below the road – a few more inches of rain and it would have been washed out entirely. My father and grandfather arranged to have the old culvert replaced with a larger 20″ plastic one – we determined that the old one had lasted over forty years.

More dramatic still, we got word that a small tornado or microburst had touched down on the opposite end of the island, and on my way out of town I poked down Bay Point road to check it out. Indeed, just past Don Wilson’s former chicken barn on the west side of the road, a swath of destruction lay down the side of a hill, with great stout oak trees uprooted or broken off rudely halfway up the trunk. Nearby some trees had been knocked over onto somebody’s trailer. Not being from tornado country, I have never seen the destructive aftermath of such a wild piece of weather.

As I understand it, climate scientists predict that global warming will lead to more frequent and more destructive extremes of weather, and while it’s of course impossible to attribute any one event to climate change, I can’t help but feel a bit under siege. I can take some measures of prudence – staking out the young apples and peaches, clearing trees away from the fence lines, keeping sod on the fields as much as possible; girding the streambanks and crossings with stonework – but all of this may be easily overcome, if it decides to rain 10 inches in one crazy storm, or if a ridiculous warm spell causes the buds to break in February. Perhaps we’ll gain some protection from our proximity to the ocean’s moderating influence, but for the most part our little farm faces in microcosm the same looming danger as the planet as a whole.

Low-impact forestry, and a good weekend’s work

February 21, 2010

Beautiful late winter weather this weekend, and I took advantage, making a solid dent in the remaining selective thinning for the high-octane maple trees.  This is an ongoing project to plant a string of sugar maples that have been specially selected by researchers at Cornell to produce a higher concentration of sugar in the sap.  We’ve located these trees along the south side of a stone wall heading down towards the water, with a sufficient slope that eventually we will be able to run a tube system to collect the sap.  Now, I will be an old, old man by the time these trees are ready to be tapped, but somehow that doesn’t seem to dissuade me.  Besides, in the meanwhile, the project improves the woodland, produces firewood for low-carbon heating, and gets me much needed exercise.   We’ve got our low-impact forestry technique pretty well worked out at this point, so I thought I’d describe it in some detail.

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Sugaring season soon; high-efficiency evaporator concepts

February 14, 2009

It’s definitely still winter here, but if you’re feeling optimistic you can imagine that it’s starting to slip away.  Days are longer, sometimes high temps over 30, and crusty old snow in the woods pockmarked by deer tracks – puts me in mind of the start of sugaring season.  It is said that during some period of blockade (perhaps the war of 1812) Benjamin Franklin floated a plan to make the US independent of tropical sugar by vastly expanding maple syrup production.  It’s an interesting concept; by my best napkin estimate an acre of sugarbush can produced enough calories to feed a person for a year – not as efficient as most field crops, but a lot less work and a lot less environmental upset.  To make this any kind of reality we would however need a much more efficient way to do the evaporation, as compared to the primitive wood and oil-fired evaporator technology now in use.

We don’t sugar here in NH (small town lot with no maple trees), but it was a fixture of the season growing up in Maine when I was a kid.  We had a small Leader evaporator made from a welded-up oil drum with a galvanized sap pan that we’d operate outdoors, producing 5-15 gals per year from around a hundred red maple taps.  It’s classic New England, but from an engineering perspective it seemed really inefficient.  The single-wall steel firebox shed most of its heat out the sides, the combustion was not well-controlled, and the wood used was typically marginally dry softwood slabs or other low grade stuff that wasn’t worth burning as stovewood.  More fundamentally, a huge amount of recoverable heat goes up in steam – about 2200 joules per gram.  The small home evaporator systems make only the most pathetic attempt at recovering the energy in the steam – a preheater pan sits over around 20% of the evaporator – and ironically the condensate that drips off the preheater falls right back into the pan.  So the first step in improving the efficiency would be to make sure to condense all the steam possible onto a heat exchanger delivering the cold sap to the evaporator – and arrange for the condensate not to fall back into the pan.  Still, even if you delivered the maximum amount of heat possible into the cold sap (around 420 J/g to raise it from0C to 100C) you would only have recovered around 20% of the available energy in the steam.  To really boost efficiency, you need to use the steam to boil more sap.  The problem is that the steam will only condense on surfaces colder than 100C – and you need a temperature higher than 100C to drive heat into boiling sap (because sap contains sugar, it boils at a temperature slightly above 100C at one atmosphere).  This could be accomplished with some kind of refrigeration cycle, but that’s too complex for hard-times engineering.   Also energetically efficient but similarly complex is the recent adoption of reverse osmosis by sugarmakers, with attendant tending of  finicky high pressure pumps and delicate membranes. What’s called for is a relatively simple, elegant, robust solution in the (quite literally) steampunk style (also cf. handy apocalypse guide) .

One solution is to condense the primary steam against a secondary evaporator, the contents of which (sap at lower sugar concentration) are held below atmospheric pressure.  This is a convenient way of lowering the boiling point.  This is not a revolutionary concept; I have demonstrated it (sort of in reverse) by boiling water on the lid of my pressure cooker – the steam within the cooker is condensing on the lid at a temperature well above 100C due to elevated internal pressure of about 2 atm absolute, such that the temperature of the lid itself is sufficiently above 100C to initiate vigorous pool boiling of pure water on its surface.   Naturally, the condensate from the secondary evaporator would have to be pumped out of that chamber; a mechanical pump would certainly do, but in the spirit of low-energy passive design it occurs to me that at least on the coast of Maine (and in many hilly regions where syrup is produced) it is not difficult to find 32 feet of vertical relief; a stable vacuum of the desired level could be established by maintaining a fluid column of condensate in a tube and controlling its escape from the secondary condensate sump with a float valve.  A glance at a steam table indicates that a pressure of around 0.6 atm is sufficient to decrease the boiling point of water by around 15C, which should be sufficient to drive boiling in the secondary evaporator.   The reduced-pressure secondary evaporator also provides a convenient means of drawing fresh sap into the system – again regulated by a float valve.  On the other hand, the partially concentrated syrup must of course be pumped from the secondary evaporator into the (atmospheric) primary evaporator.  This could be accomplished by a hand pump if the system is monitored steadily (the amount of shaft work required being relatively modest) or in concession to modern technology a small diaphragm pump.  Condensate (either from the primary or secondary evaporator) would again be used to preheat the incoming feed of sap.

By means of this dual-stage evaporator, the energy required to make syrup could be decreased from approximately 2600 J/gram of sap plus losses to around 1100 plus losses.  Of course, still greater efficiency could be achieved by condensing the evaporated steam from the secondary evaporator against the underside of a tertiary evaporator (operating at perhaps 0.2psi absolute) and so on ad infinitum.  A primary boiler stage operated at elevated pressure is also conceivable.  But a doubling (or better, given concomitant thermal conservation measures of a more pedestrian nature) of evaporating efficiency as an initial goal seems reasonable.  I have not pieced together all of the mechanical and fluidic aspects in my head, but my dim mental picture is quite satisfying, combining the favorable aesthetics of the African Queen with that of a backwoods moonshine still.  Also, the potential for catastrophic explosion is almost too good to pass up.

Snow, Farmi winch

January 28, 2009

Well, the good lord has seen fit to bless us with another foot of snow, so I’m sitting by the fire with a glass of cider and a slab of chocolate cake, contemplating the state of the world.  We went up to Maine last weekend, and on Saturday Joshua and I did some work in the woodlot to prepare for transplanting the sugar maple trees, and in the process tried out Dave’s new Farmi PTO forestry winch.  This is a really neat contraption that hooks up to the 3-point hitch of our 25hp tractor and draws power from the splined PTO shaft that protrudes from the back of the tractor.  Its basic function is to winch logs out of the woods with its 150′ cable, and we found that it works pretty nicely.  We felled a 10 inch maple and three oaks (up to perhaps 14″ diameter) that I had previously selected for thinning to make room for the string of Cornell University improved sugar maple trees.  Our typical practice is to buck up firewood trees into 4 foot lengths (if up to about 8-10″ diameter) or 16″ lengths (if larger), load them onto a trailer, unload them in our traditional firewood-fitting spot near the house, then subsequently buck, split, stack, and trailer them once again to the woodshed or basement.  With the winch, we limbed them where they fell, then pulled them tree-length to a new fitting yard we established by the upper cabin.  This saves us the step of trailering the wood to the yard, and gives us a couple of options.  We can fit and stack it right where it is, transporting it once more to the woodshed.  Alternatively, since we have had more than enough hardwood for our own needs recently, my dad can cut it to 10 foot lengths, load it in his dump trailer with the small excavator, and sell it to folks who are willing to fit it themselves for a discount relative to the fitted price.

As to the performance of the winch itself I would rate it as thoroughly satisfactory given the conditions.  There was about 8″ of old snow on the ground, with the ground frozen underneath, so piloting the tractor over uneven ground was an approximate affair, with extensive use of differential lock and left and right wheel brakes.  The winch itself has a dozer blade which helps to prevent the tractor from backsliding, which was surprisingly effective given the icy ground conditions.  The cable takeup is activated by a clutch by way of a lanyard, and the clutch tension is set about right – if the log hits an obstacle, the winch slips before the engine stalls as long as it’s idled up reasonably high.  The most serious limitation was that the tractor did not have enough traction to actually skid the large timber on the snowy ground – I had to make the entire ~500 foot trip to the yard using about 4 sequential pulls.  This wasn’t too bad; I could reel one in, then freespool the cable out and hitch it to the choker on the next one.  Once they were all drawn up short, I’d freespool the winch again and pull the tractor ahead.  We could pull the logs up a fairly steep incline, over an old stone wall, etc – only a direct hit on a stump would bring things to a halt.  We should have had a peavy on hand to help guide things along, but we didn’t think of it so had to use brute force.  If the ground conditions were dry (or if we had Canadian chains for the tractor) we would have been able to skid the logs directly, saving time.  We also would have benefitted from having some purpose-made 5/16 choker chains, rather than the all-purpose 3/8″ tow chains that we had.  We also noted that it’s important to leave strategically placed trees to be cut last, in order to take the brunt of the logs as they pass, sparing the keeper trees from damage to the trunks near the roots.  But especially under frozen ground conditions and with careful planning, the Farmi winch seems to be a useful tool that promises to substantially streamline harvesting firewood and responsible woodlot management.

Summer orchard progress

July 24, 2008

Life has been busy what with lots of solar cell engineering and a renewed focus on the fiddle (I’ve added a couple really cool, rhythmic minor key tunes – Cliffs of Moher and Morrison’s, and some old favorites, including Spootiskerry, Silver Spear, Drowsy Maggie, and Julia Delaney), but I’ve been up to work on the orchard a couple of times over the last few weeks.  I mowed down the rye/vetch mix, which had grown up into a massive tangle of verdant vines almost as tall as I am.  The orchard grass/clover/timothy mix I put down has come up pretty well, though it’s thin in the drier spots because of the lack of rain.  I tried out the new irrigation pump, which I hooked up to the black pipe I installed earlier in the year.  The tiny four cycle motor can put out a nice stream from a garden hose even at a pretty low idle, and it handily provides for two hoses at full bore.  It appears as if it could run at least four rainbirds simultaneously if I ever wanted to water the whole half acre, though to save water I probably won’t do that except in emergencies (e.g getting a cover crop to sprout in a dry spell).  It makes it pretty easy to dump five or ten gallons on each tree in short order.  I also patrolled the fenceline, pulling weeds that were in danger of shorting the fence, and put a coat of white paint with rotenone on the bases of the apple tree trunks to ward off borers.  That mixture is an experiment; the suggested mix of white paint and drywall compound did not seem to deter the borers, though it did make it easier to see the damage they inflict.   An infestation of Japanese beetles started munching on the trees, so my mom put out some pheremone traps that seemed to collect them pretty well.  The trees generally seem to be doing well; most have added 8-12″ of new growth despite being transplanted, and I had to release the species nametags that came on them, to keep them from constricting the stems as they expand.

I also dragged a couple of cords of four foot firewood out of the woods from the maple area with help from my Mom and my cousin Matthew using the cordwood hauler, and put it on my grandfather’s firewood pile.  I put a few tanks of gas through the chainsaw clearing further down the hill along the stone wall for the maples, and helped my folks bush-hog the fields (gotta get some sheep to make use of all that grass).  My cousin and I also cut down a couple of crooked wild apple trees and a dying pine to make room for a giant compost pile behind the pole barn, where roots from the orchard clearing and crooked softwood chunks can slowly decay to mulch over the coming decades.  All in all things are going and growing well, and I look forward to seeing how the trees look on Labor Day weekend.

In the ground!

April 21, 2007

The first 22 fruit trees of the new orchard were planted on Saturday the 14th.  We were joined by 8 friends who came up to help with the planting.  A storm had blown through mid-week, but fortunately only about an inch of snow fell in Georgetown.  My folks had tarped the nursery bed before the storm, and when we pulled the tarps the soil was in good condition despite the snow and rain.  So, on Saturday morning I disked down the bed and ran the spring harrow over it a couple of times, then everyone set to work digging holes, planting the trees, and watering them in.  In addition to the fruit trees we also planted twenty of the Cornell maple cuttings, which will hopefully provide us high-octane sap in a few decades.  We also did some clearing, moved some brush and manure, gathered seaweed for mulch/fertilizer, and stacked some firewood for my grandparents, who aren’t quite as spry as they once were.  At the end of the day we extended a nearby fence to protect the young trees from deer.  Here’s a photo of the action:

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A big storm was scheduled to hit late Sunday, so everyone took off mid-day for Boston, after a walk on the beach at Reid park.  As it turned out, the coast got mostly rain, while Alexis and I headed for New Hampshire through the slush.  The storm knocked the power out on the North End for several days, but they are pretty much used to that.  And, finally, spring has arrived, with sun and temps in the 60s.  The new orchard site should finally dry out, to the point that we can hopefully work the soil and plant the cover crop when my sister comes in May.

Hearty thanks to everyone who lent a hand; we should start getting apples around 2012.

Trees Arrived; Slow Spring

April 10, 2007

It’s been a slow, cold spring.  Alexis and I are just back from a long weekend in Maine, and it never broke 45 degrees the whole time we were there.  A late-season snowstorm dropped 10″ of snow middle of last week, and much of it was still on the ground when we arrived.  The snow fell heavy and wet, and the wind was nearly calm, so it built up on trees, and falling limbs caused minor damage to some buildings.  It killed the power for three days – when there’s a big storm the power crews take a long time to get down the back roads.  The maple sap is usually done flowing by this time of year, but almost 60 gallons flowed on Sunday.  Another storm is blowing in on Thursday; hopefully it’s rain but they say it might be some snow as well.

Despite the cold temperatures and limited sunshine, the snow melted appreciably while we were there and is coming off the fields, but it persists in the woods.   The apple trees arrived from Fedco today, along with 4 peaches and 2 cherries.  I’ve already got 50 pounds of Peas/Vetch/Oats mix for the new orchard spot, as soon as the ground is dry enough to work and seed, and clover to spread between the new trees.  I was going to do some prep for the planting this last weekend, but with things still pretty damp I focused on woods work, cutting crummy fir and swamp maple along the westward stone wall that leads down to the cove.  The supercharged sugar maples from Cornell will go along either side of the stone wall when the clearing is done.

Orchard Weekend

March 3, 2007

We’ve set the date for the first North End Orchard Weekend in April; I’ll send invites out soon, or write me email for more info. Highlights:

  • Sixteen heirloom apple trees, four peaches, and two cherry trees will be planted in the nursery bed
  • The new orchard site will be cleaned up, turned over, and seeded with soil-building cover crop
  • Fencing needs to be moved to protect the new trees, possibly also fencing around the new orchard
  • Twenty high-octane sugar maples will be planted, either in the nursery or along the stone wall down to the cove
  • Further orchard clearing, brush chipping, and compost-making as time permits
  • Meet the goats (Willow and Larry), three new dogs (Kermit, Zoey, and Lacey) and check out Dave’s new excavator

We’ll provide grub and (rustic) accommodation, also a tank of last year’s hard cider as well as apples and fresh cider (if we can find any decent stuff), and music (if people bring instruments). It will be a good time. Too cold to swim, but there are usually canoes around.

Stumped!

December 21, 2006

Tuesday I drove up to Maine to help out with the stumping of the orchard site.  My dad (who is a building contractor) called on Dick Holbrook, his usual dirt contractor, and Dick’s guy Vance brought a big John Deere machine down to do the job.  Vance pulled out a couple dozen stumps, including a couple big maples 2 feet or more in diameter, broke up and moved a mound of rocks, and consolidated all the brush into one big pile.  Here he is at work:

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He buried the stumps off in the woods to the southwest, and piled the rocks (probably five or more cubic yards) in a big heap at the north edge of the orchard.  There are plenty of nice ones there, in case Holly ever wants to practice his dry stone laying skills.  The story of the rock pile is a mystery; there was a big grassy mound with rocks and bricks sticking out in the center of the orchard that we assumed was an old foundation, and the area is peppered with old wild apple trees that are presumably descended from the originals that the old timers kept.  But when we got into it, though there were some very nice rectilinear blocks as well as the usual rounded boulders, we saw no glass, metal, or any other signs that there had been a structure there.  There is barbed wire mixed in with the stone wall around the orchard perimeter, so someone was definitely trying to keep something in or out, but I feel that if there had been a significant structure there we would have seen more evidence.  At this point I have to conclude that if there was a structure there it must have been minimal (perhaps a cowshed of log walls) or perhaps it was moved away. 

Anyway, at the end of the day the stumps were gone, the mound was flattened out, and the site is ready for the brush to be burned and the soil prepared for planting.  While Vance was working, I cleared some undergrowth to the east of the orchard, and started thinning an area for the new sugar maples along the stone wall that leads down to the cove.  I’m cutting out all of the trashy fir and most of the red maples and leaving the straight oaks.  I understand that maples are relatively tolerant of partial shade, so I plan to let the oaks grow up a bit more while the maples get their start, to avoid clear-cutting an ugly gash in the hillside.  The maple cuts remarkably quickly with a sharp chain, and the work is pleasant in the cold with the sun out.  Vance says the excavator uses about 10 gallons of diesel in a day, and I probably burned a quart or so of 2 cycle mix in the chainsaw.  The power of petroleum is remarkable; the work that excavator did in a day would probably have taken the old timers a month with two men and a team of oxen, and I’m sure it would have taken me a week to do the amount of cutting that I accomplished in a few hours with the Stihl.

 Next steps: Burn the brushpile; yark out the remaining roots, add lime and goat manure (and possibly seaweed from the cove, or some other goodness), and prepare the soil for a cover crop; perhaps peas/vetch/oat mix, which is said to work well under typical Maine conditions.  Here’s how the site looks now:

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Maple Project

December 3, 2006

The maple trees that grow on Georgetown Island are mostly Red Maple (Acer rubrum), cousins to the more famous Sugar Maple (A. saccharum).  We tapped them for syrup when I was a kid, but the sugar content of Red Maple sap is only half that of the Sugar Maple, and it was hard work to get even a few gallons of syrup per year.  I’m planning to change all that, if not for me than for future generations, by planting a swath of sugar maples on the west-facing slope running down to Robinhood Cove.  There is already a single sugar maple at the foot of the southernmost field, planted some years ago by my grandfather and waiting patiently for company.

Last winter I found a website at Cornell describing a Sugar Maple improvement program, in which researchers selected trees with a significantly higher sugar content than their neighbors and propagated them.  As it turns out, the variability in sugar content of maple sap is at least to some extent genetically determined, and the program has seeds and rooted seedlings available on a limited basis.  I corresponded with the researchers at Cornell and got a ziploc bag full of seeds from the “sweet trees” in the spring, and I germinated them in the fridge and transplanted them out in pots in the back yard over the summer.  They are now in the ground in the old pumpkin patch, waiting for me to clear some land for them on the slope west of the orchard.  I also put in a request for a dozen rooted cuttings from Cornell, which will be a surer bet genetically, though carrying an increased risk of disease susceptibility, as with any monoculture.  Hopefully these arrive in the spring and the maple project can begin in earnest.  I plan to do some thinning in the woods this winter where the trees will be going, now that the apple orchard site is clear.